docs: def _Stichlmair_flood_f(inputs, Vl, rhog, rhol, mug, voidage, specific_area,
                          C1, C2, C3, H):
      '''Internal function which calculates the errors of the two Stichlmair
      objective functions, and their jacobian.
      '''
      Vg, dP_irr = float(inputs[0]), float(inputs[1])
      dp = 6.0*(1.0 - voidage)/specific_area
      Re = Vg*rhog*dp/mug
      f0 = C1/Re + C2/Re**0.5 + C3
      dP_dry = 0.75*f0*(1.0 - voidage)/voidage**4.65*rhog*H/dp*Vg*Vg
      c = (-C1/Re - 0.5*C2*Re**-0.5)/f0
      Frl = Vl*Vl*specific_area/(g*voidage**4.65)
      h0 = 0.555*Frl**(1/3.)
      hT = h0*(1.0 + 20.0*(dP_irr/H/rhol/g)**2)
      err1 = dP_dry/H*((1.0 - voidage + hT)/(1.0 - voidage))**((2.0 + c)/3.)*(voidage/(voidage-hT))**4.65 - dP_irr/H
      term = (dP_irr/(rhol*g*H))**2
      err2 = (1./term - 40.0*((2.0+c)/3.)*h0/(1.0 - voidage + h0*(1.0 + 20.0*term))
      - 186.0*h0/(voidage - h0*(1.0 + 20.0*term)))
      return err1, err2